In a color filter used for a liquid crystal display of a full color, a pattern picture element having a light-shielding property is usually provided between the respective picture elements of R, G and B for the purposes of preventing light leakage and improving contrast.
This pattern picture element having the light-shielding property is formed by using a metal film of chromium and a material obtained by dispersing a black dye in a light-sensitive resin composition. In the case of the metal film of chromium, the metal film is deposited on a full face of a glass substrate by means of deposition, and then a resist is coated, followed by carrying out patterning and etching to subject the metal film to patterning. This method has very complicated processes and a bad yield and is costly. Meanwhile, there has been known a forming process for a pattern picture element having a light-shielding property which is provided by a light-sensitive black resin obtained by combining a light-sensitive resin composition with carbon. In this case, a film thickness of several .mu.m is required to obtain a light-shielding property to some extent, and since the present state of the art is that in preparing a color filter, the pattern picture element having the light-shielding property usually has overlapping with the R, G and B picture elements to some extent from a viewpoint of a problem on an alignment error, an unevenness is generated on the surface of the color filter. Accordingly, the actual situation is that to obtain a good flatness, a flattening layer is further provided thereon or surface grinding is carried out.
JP-A-3-209203 (the term "JP-A" as used herein means an unexamined Japanese patent application) and JP-A-4-69602 describe the processes in which a black color light-sensitive resin composition layer is coated on a full face after forming the R, G and B picture elements and exposing is carried out from the back face to form the pattern picture elements having a light-shielding property between the R, G and B picture elements. However, it is very difficult in these processes to coat the black color light-sensitive resin composition layer all over the face between the respective R, G and B picture elements in the same thickness as those of the R, G and B picture elements, and the preparation of a liquid crystal panel using a color filter prepared by these processes has the problem that a cell gap produced is not uniform to generate a display unevenness.
Further, there are many chances to see still pictures on a device using a liquid crystal display element and accordingly, a deficiency on the picture elements of the respective colors constituting a color filter is desirably zero.
However, many difficulties are accompanied in manufacturing a lot of the color filters which are completely free from a deficiency of a picture element attributable to a fine dust present and insufficient washing of a substrate in a washing process.
Thus, there has been required a correcting method for a color filter having a small number of lacked picture elements to further improve yield.
In a conventional deficiency correcting method in which a colored light-sensitive resin composition coating solution is applied to a deficiency part and exposing is carried out through a glass substrate, it has been very difficult, due to limits of a coating technique, to form a corrected picture element having a good flatness at the deficient part. Further, in the case where the deficiencies of plural colors are involved, the processes for coating a colored light-sensitive resin composition solution, exposing and developing must be repeated several times, which has generated another deficiency in some cases as well as requiring enormous labor.
Further, a colored light-sensitive resin composition layer is formed as well on a picture element having a deficiency, and if the colored light-sensitive resin composition layer provided on the picture element having the deficiency has a large transmittance in a light-sensitive wavelength region, the colored light-sensitive resin composition layer formed on the picture element is cured as well. Thus a serious non-removable defect resulted and a hue was changed.